High resolution electron microscopy with expanded features which enable the investigation of low-contrast biological specimens, examination of surface or topographic characteristics of specimens and routine transmission electron microscopy is required by a number of biomedical scientists in our institution. In addition to having a number of NIH-supported research investigations requiring high-resolution electron microscopy, we also have an active NIH-supported training grant which currently supports 11 fellows also interested in ultrastructural analyses of biomedical problems. This application requests funds from the "Biomedical Research Support Shared Instrumentation" to purchase a JEM-100 CXII electron microscope (JEOL) to be used by faculty and students associated with the School of Dentistry at this University. If this instrumentation is made available, every effort will be made to also share this resource with faculty and students on the Main Campus of this University.